For uses denoted with a “P” in Section 32-171 (Use Group VII – general use allowances), the provisions of this Section shall apply. In C1 or C2 Districts, as well as in C4 through C8 District, laboratories shall be limited to those that comply with the standards set forth in Section 427 of the New York City Building Code, or its successor. However, other laboratories may be permitted by special permit of the City Planning Commission, as set forth in Section 74-171 (Laboratories).